Buggy code:
abstract class IntegrationTestCase extends TestCase { protected static final Joiner LINE_JOINER = Joiner . on ( '\n' ) ; protected static final List < SourceFile > DEFAULT_EXTERNS = ImmutableList . of ( SourceFile . fromCode ( "externs" , IntegrationTestCase . LINE_JOINER . join ( "var<seq2seq4repair_space>arguments;" , "var<seq2seq4repair_space>undefined;" , "var<seq2seq4repair_space>Math;" , "var<seq2seq4repair_space>isNaN;" , "var<seq2seq4repair_space>Infinity;" , "//**<seq2seq4repair_space>@interface<seq2seq4repair_space>*//" , "var<seq2seq4repair_space>Iterator;" , "//**<seq2seq4repair_space>@interface<seq2seq4repair_space>*//" , "var<seq2seq4repair_space>Iterable;" , "//**<seq2seq4repair_space>@interface<seq2seq4repair_space>@extends<seq2seq4repair_space>{Iterator}<seq2seq4repair_space>@extends<seq2seq4repair_space>{Iterable}<seq2seq4repair_space>*//" , "var<seq2seq4repair_space>IteratorIterable;" , "//**<seq2seq4repair_space>@interface<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>IArrayLike()<seq2seq4repair_space>{};" , "//**<seq2seq4repair_space>@constructor<seq2seq4repair_space>*//" , "var<seq2seq4repair_space>Map;" , "" , "//**<seq2seq4repair_space>@constructor<seq2seq4repair_space>*//<seq2seq4repair_space>function<seq2seq4repair_space>Window()<seq2seq4repair_space>{}" , "//**<seq2seq4repair_space>@type<seq2seq4repair_space>{string}<seq2seq4repair_space>*//<seq2seq4repair_space>Window.prototype.name;" , "//**<seq2seq4repair_space>@type<seq2seq4repair_space>{string}<seq2seq4repair_space>*//<seq2seq4repair_space>Window.prototype.offsetWidth;" , "//**<seq2seq4repair_space>@type<seq2seq4repair_space>{Window}<seq2seq4repair_space>*//<seq2seq4repair_space>var<seq2seq4repair_space>window;" , "" , "//**<seq2seq4repair_space>@nosideeffects<seq2seq4repair_space>*//<seq2seq4repair_space>function<seq2seq4repair_space>noSideEffects()<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*<seq2seq4repair_space>@nosideeffects" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Widget()<seq2seq4repair_space>{}" , "//**<seq2seq4repair_space>@modifies<seq2seq4repair_space>{this}<seq2seq4repair_space>*//<seq2seq4repair_space>Widget.prototype.go<seq2seq4repair_space>=<seq2seq4repair_space>function()<seq2seq4repair_space>{};" , "//**<seq2seq4repair_space>@return<seq2seq4repair_space>{string}<seq2seq4repair_space>*//<seq2seq4repair_space>var<seq2seq4repair_space>widgetToken<seq2seq4repair_space>=<seq2seq4repair_space>function()<seq2seq4repair_space>{};" , "" , "function<seq2seq4repair_space>alert(message)<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*<seq2seq4repair_space>@implements<seq2seq4repair_space>{IArrayLike}" , "<seq2seq4repair_space>*<seq2seq4repair_space>@return<seq2seq4repair_space>{!Array}" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{...*}<seq2seq4repair_space>var_args" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Array(var_args)<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*<seq2seq4repair_space>@return<seq2seq4repair_space>{number}" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{*=}<seq2seq4repair_space>opt_n" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Number(opt_n)<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*<seq2seq4repair_space>@return<seq2seq4repair_space>{string}" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{*=}<seq2seq4repair_space>opt_s" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>String(opt_s)<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*<seq2seq4repair_space>@return<seq2seq4repair_space>{boolean}" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{*=}<seq2seq4repair_space>opt_b" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Boolean(opt_b)<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*<seq2seq4repair_space>@return<seq2seq4repair_space>{!TypeError}" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{*=}<seq2seq4repair_space>opt_message" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{*=}<seq2seq4repair_space>opt_file" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{*=}<seq2seq4repair_space>opt_line" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>TypeError(opt_message,<seq2seq4repair_space>opt_file,<seq2seq4repair_space>opt_line)<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{*=}<seq2seq4repair_space>opt_value" , "<seq2seq4repair_space>*<seq2seq4repair_space>@return<seq2seq4repair_space>{!Object}" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Object(opt_value)<seq2seq4repair_space>{}" , "Object.seal;" , "Object.defineProperties;" , "//**<seq2seq4repair_space>@type<seq2seq4repair_space>{!Function}<seq2seq4repair_space>*//" , "Object.prototype.constructor;" , "" , "//**<seq2seq4repair_space>@typedef<seq2seq4repair_space>{?}<seq2seq4repair_space>*//" , "var<seq2seq4repair_space>symbol;" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{string}<seq2seq4repair_space>s" , "<seq2seq4repair_space>*<seq2seq4repair_space>@return<seq2seq4repair_space>{symbol}" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Symbol(s)<seq2seq4repair_space>{}" , "" , "//**" , "<seq2seq4repair_space>*<seq2seq4repair_space>@param<seq2seq4repair_space>{...*}<seq2seq4repair_space>var_args" , "<seq2seq4repair_space>*<seq2seq4repair_space>@constructor" , "<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Function(var_args)<seq2seq4repair_space>{}" , "//**<seq2seq4repair_space>@param<seq2seq4repair_space>{...*}<seq2seq4repair_space>var_args<seq2seq4repair_space>*//" , "Function.prototype.call<seq2seq4repair_space>=<seq2seq4repair_space>function<seq2seq4repair_space>(var_args)<seq2seq4repair_space>{};" , "" , "//**<seq2seq4repair_space>@constructor<seq2seq4repair_space>*//" , "function<seq2seq4repair_space>Arguments()<seq2seq4repair_space>{}" ) ) ) ; protected List < SourceFile > externs = IntegrationTestCase . DEFAULT_EXTERNS ; protected Compiler lastCompiler ; protected boolean normalizeResults = false ; @ Override public void setUp ( ) { } protected void testSame ( CompilerOptions options , String original ) { } protected void testSame ( CompilerOptions options , String [ ] original ) { } protected void test ( CompilerOptions options , String original , String compiled ) { } protected void test ( CompilerOptions options , String [ ] original , String [ ] compiled ) { Compiler compiler = compile ( options , original ) ; <START_BUG> assertEquals ( ( ( ( ( "Expected<seq2seq4repair_space>no<seq2seq4repair_space>warnings<seq2seq4repair_space>or<seq2seq4repair_space>errors\n" + "Errors:<seq2seq4repair_space>\n" ) + ( Joiner . on ( "\n" ) . join ( compiler . getErrors ( ) ) ) ) + "Warnings:<seq2seq4repair_space>\n" ) + ( Joiner . on ( "\n" ) . join ( compiler . getWarnings ( ) ) ) ) , 0 , ( ( compiler . getErrors ( ) . length ) + ( compiler . getWarnings ( ) . length ) ) ) ; <END_BUG> Node root = compiler . getRoot ( ) . getLastChild ( ) ; Node expectedRoot = parseExpectedCode ( compiled , options , normalizeResults ) ; String explanation = expectedRoot . checkTreeEquals ( root ) ; assertNull ( ( ( ( ( ( ( ( "\n" + "Expected:<seq2seq4repair_space>" ) + ( compiler . toSource ( expectedRoot ) ) ) + "\n" ) + "Result:<seq2seq4repair_space>" ) + ( compiler . toSource ( root ) ) ) + "\n" ) + explanation ) , explanation ) ; } protected void test ( CompilerOptions options , String original , DiagnosticType warning ) { } protected void test ( CompilerOptions options , String original , String compiled , DiagnosticType warning ) { } protected void test ( CompilerOptions options , String [ ] original , DiagnosticType warning ) { } protected void test ( CompilerOptions options , String [ ] original , String [ ] compiled , DiagnosticType warning ) { } protected void testParseError ( CompilerOptions options , String original ) { } protected void testParseError ( CompilerOptions options , String original , String compiled ) { } protected void test ( CompilerOptions options , String [ ] original , String [ ] compiled , DiagnosticType [ ] warnings ) { } protected void checkUnexpectedErrorsOrWarnings ( Compiler compiler , int expected ) { } protected Compiler compile ( CompilerOptions options , String original ) { } protected Compiler compile ( CompilerOptions options , String [ ] original ) { } protected Node parseExpectedCode ( String [ ] original , CompilerOptions options , boolean normalize ) { } protected Node parse ( String [ ] original , CompilerOptions options , boolean normalize ) { } abstract CompilerOptions createCompilerOptions ( ) { } }

Fix:
assertEquals ( ( ( ( ( ( "Expected<seq2seq4repair_space>no<seq2seq4repair_space>warnings<seq2seq4repair_space>or<seq2seq4repair_space>errors\n" + "Errors:<seq2seq4repair_space>\n" ) + ( Joiner . on ( "\n" ) . join ( compiler . getErrors ( ) ) ) ) + "\n" ) + "Warnings:<seq2seq4repair_space>\n" ) + ( Joiner . on ( "\n" ) . join ( compiler . getWarnings ( ) ) ) ) , 0 , ( ( compiler . getErrors ( ) . length ) + ( compiler . getWarnings ( ) . length ) ) ) ;